Cranberry Juice: How to Carefully Assess its Potassium and Sugar Content 

Cranberry Juice: How to Carefully Assess its Potassium and Sugar Content

Written by Bhavini Patel and reviewed by Emily Campbell

People often recommend drinking cranberry juice to prevent and treat urinary tract infections (UTIs) in women; however, a meta-analysis revealed that the amount of proanthocyanidins—the chemical compound found in cranberries that prevents bacteria from infesting the lining of the bladder— in most cranberry juices is too low to have a meaningful effect in fighting UTIs (Jepson et al., 2012). 

Those living with chronic kidney disease may choose to drink cranberry juice due to its low potassium content. A study by Jessica Krefting, RD, investigated various cranberry juices and products to identify quantities of potassium in each (2017). The findings reveal that potassium content varies drastically between products: from as low as 50 mg to over 200 mg in servings measuring 8 oz. 

Krefting reports that juices labelled as “100% Juice” and “Juice Blend” (a mixture of cranberry juice and at least one other fruit juice) contained the highest levels of potassium, whereas those labelled as “Juice Drinks” contained lower levels. Unfortunately, the latter did not depict better options as they are made of only 15% cranberry juice, while the rest is a mix of filtered water and sugar. 

Consuming high quantities of sugar is ill-advised for the general population, but especially for people affected by kidney disease who often also have diabetes. According to the study, a serving of 8 oz of cranberry juice comprises upward of 30 grams of carbohydrates – which may lead to higher blood sugar levels. 

The following table reports some of the nutritional findings from the study: 

Product NameSizePotassium (mg) Sodium (mg)Carbs (g)Sugar (g)
Diet Cranberry Juice Drink 8 oz20 mg20 mg2 g<1
Kirkland Ocean-Spray 100% Juice Cranberry Premium 8 oz50 mg15 mg30 g30 g
Light Cranberry Juice 8 oz90 mg40 mg11 g11 g
100% Juice Cranberry 8 oz190 mg15 mg28 g28 g
White Cranberry Juice Drink 8 oz25 mg35 mg26 g26 g
Raw Cranberries1 cup88 mgN/AN/AN/A
Please note that the information above concerns US products. It is important to read food labels in Canada to accurately assess nutritional values. 

Although these findings suggest that cranberry juice may not be as beneficial as we once thought, Krefting proposes that people with kidney disease can still safely enjoy small amounts of cranberry juice and products without compromising their kidney function. She advises the following: 

  • Read nutrition labels carefully: opt for diet cranberry options as these are sugar free.  
  • Choose only a small quantity of cranberry juice to replace other fluids but be mindful about your fluid targets. 
  • Check the nutrition facts table and ingredient list for potassium sources.  

Krefting also notes that cranberry juice and products do not provide significant health benefits (nutritious and medical) in the recommended quantities, but they help add delicious flavour to many recipes. Check out the following Kidney Community Kitchen recipes for inspiration: 

View more of our cranberry recipes

Consult your renal dietitian to learn more about incorporating cranberry juice into your diet. 

This article is based on  Cranberry Juice: What Is the Potassium Story?. Journal of Renal Nutrition, 27(1), e1-e4. Krefting, J. (2017). doi: https://doi.org/10.1053/j.jrn.2016.10.002  

 Reference  

Jepson, R. G., Williams, G., & Craig, J. C. (2012). Cranberries for preventing urinary tract infections. Cochrane database of systematic reviews, (10). doi: https://doi.org/10.1002/14651858.CD001321.pub5